Cosmic-ray anisotropy in the north–south direction
For the study of a cosmic-ray anisotropy in the north–south direction, the day-to-day variation of the difference (N–S) of cosmic-ray neutron intensities between the arctic and the antarctic was examined with respect to solar rotations. Harmonic analysis on the variation of the intensity difference...
Published in: | Canadian Journal of Physics |
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Main Authors: | , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Canadian Science Publishing
1968
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Subjects: | |
Online Access: | http://dx.doi.org/10.1139/p68-363 http://www.nrcresearchpress.com/doi/pdf/10.1139/p68-363 |
Summary: | For the study of a cosmic-ray anisotropy in the north–south direction, the day-to-day variation of the difference (N–S) of cosmic-ray neutron intensities between the arctic and the antarctic was examined with respect to solar rotations. Harmonic analysis on the variation of the intensity difference shows the existence of a recurrent variation with half the period of a solar rotation. Such a recurrent variation is closely connected with the rapid phase changes of the cosmic-ray diurnal variation during a solar rotation. Regarding the sectored structure of solar wind reported by Wilcox and Ness, the intensity difference (N–S) increases when the earth is passing near a boundary from the (+) sector into the (−) sector, while it decreases near the other boundary. This N–S anisotropy of cosmic rays seems to be caused by the transitional change of cosmic-ray trajectories near the sector boundary and by the spatial distribution of cosmic-ray flux. |
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